Skip to main content
Article thumbnail
Location of Repository

Leg disorders in broiler chickens : prevalence, risk factors and prevention

By Toby G. Knowles, Steve C. Kestin, Susan M. Haslam, Steven N. Brown, Laura E. Green, Andrew Butterworth, Stuart J. Pope, Dirk Pfeiffer and Christine J. Nicol


Broiler (meat) chickens have been subjected to intense genetic selection. In the past 50 years, broiler growth rates have increased\ud by over 300% (from 25 g per day to 100 g per day). There is growing societal concern that many broiler chickens have impaired\ud locomotion or are even unable to walk. Here we present the results of a comprehensive survey of commercial flocks which\ud quantifies the risk factors for poor locomotion in broiler chickens.We assessed the walking ability of 51,000 birds, representing 4.8\ud million birds within 176 flocks.We also obtained information on approximately 150 different management factors associated with\ud each flock. At a mean age of 40 days, over 27.6% of birds in our study showed poor locomotion and 3.3% were almost unable to\ud walk. The high prevalence of poor locomotion occurred despite culling policies designed to remove severely lame birds from\ud flocks. We show that the primary risk factors associated with impaired locomotion and poor leg health are those specifically\ud associated with rate of growth. Factors significantly associated with high gait score included the age of the bird (older birds), visit\ud (second visit to same flock), bird genotype, not feeding whole wheat, a shorter dark period during the day, higher stocking density\ud at the time of assessment, no use of antibiotic, and the use of intact feed pellets. The welfare implications are profound. Worldwide\ud approximately 261010 broilers are reared within similar husbandry systems.We identify a range of management factors that could\ud be altered to reduce leg health problems, but implementation of these changes would be likely to reduce growth rate and\ud production. A debate on the sustainability of current practice in the production of this important food source is required

Topics: SF
Publisher: Public Library of Science
Year: 2008
OAI identifier:

Suggested articles


  1. (2003). A comparison between leg problems in Danish and Swedish broiler production.
  2. (2002). A novel technique for objectively assessing lameness in broiler chickens.
  3. (2002). A review of the aetiology and pathology of leg weakness in broilers in relation to welfare. doi
  4. (2001). Behaviour and leg weakness in different broiler breeds.
  5. (2006). Behaviour and welfare of broiler chicken. doi
  6. (2004). Chicken welfare is influenced more by housing conditions than by stocking density. doi
  7. (2005). Compassion in World Farming doi
  8. (2002). Dehydration and lameness in a broiler flock.
  9. (1999). Developmental instability and light regime in chickens. doi
  10. (1999). Different commercial broiler crosses have different susceptibilities to leg weakness. doi
  11. (1999). Effect of carprofen on lameness in broiler chickens. doi
  12. (1999). Effects of dietary roxarsone supplementation, lighting program, and season on the incidence of leg abnormalities in broiler chickens. doi
  13. (1992). Farm Animal Welfare Council doi
  14. (2000). Issues arising from genetic selection for growth and body composition characteristics in poultry and pigs.
  15. (1999). Meal feeding is more effective than early feed restriction at reducing the prevalence of leg weakness in broiler chickens. doi
  16. (2001). Monitoring leg problems in broilers: a survey of commercial broiler production in Denmark. doi
  17. (1989). Photoperiodic effects on performance and leg abnormalities in broiler chickens. doi
  18. (2007). Public attitudes to the welfare of broiler chickens.
  19. (2001). Relationships in broiler chickens between lameness, live weight, growth rate and age. doi
  20. (2007). Release IP/07/630.
  21. (2000). Scientific Committee on Animal Health and Animal Welfare doi
  22. (2000). Self selection of the analgesic drug carprofen by lame broiler chickens. doi
  23. (2000). The behaviour of broiler chickens and its modification by lameness. doi
  24. (2007). The impact of nutrient density, feed form, and photoperiod on the walking ability and skeletal quality of broiler chickens. doi
  25. (1992). The prevalence of leg weakness in broiler chickens assessed by gait scoring and its relationship to genotype. doi
  26. (2006). Welfare of broilers: a review. doi

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.